Keeping Out Street Noise / Sound-Reducing Windows

Dear Audiogon:

In my urban (Chicago) home setting, the single biggest negative impact on my listening enjoyment is the outside noise from the street that intrudes through the windows of my listening room, which faces the street. I don't have the option of moving to a room that faces the alley, and I'm trying to think of ways to damp the street noise. Mostly it's cars with no muffler/under-performing muffler (or "high performance" street racer/ricer style "upgraded" mufflers, which are in a class of pain all their own). And of course the "boom cars" cruising by slowly, to make sure I don't fail to appreciate every note of the driver's current obsession. And of course the usual urban mix of sirens, shouting, horn honks, ice cream trucks, car alarms, etc. (And no, I have no interest in moving to a quiet suburb. Been there, done that for many years, and not inclined to repeat.)

I'm thinking maybe the answer is to get sound-reducing windows. I previously installed Loewen Tranquility windows in a home I used to own that, while in the overall quiet suburb of Libertyville, IL, had a rail line running along the back lot line of my home, and the trains were signaled to sound their horns directly behind my house (about 200 feet from my bedroom) to warn vehicles at a nearby grade crossing. Also had a massive tree, full to exploding with starlings and other chirping avians, that overhung the roof right next to the bedroom windows. I had the Tranquility windows installed, and they did a very decent job, especially with the chirping birds (they cut the high frequencies much better than the low, as I would have expected). It was always fun to demonstrate them by cranking them open and closed and hearing the bird-chirp din alternate between overwhelming (when open even a crack) and completely unhearable (when closed). It was a lot like that scene in Ace Ventura: Pet Detective where the hero demonstrates the sound-blocking ability of a murder victim's glass balcony doors (minus the hilarity).

For those who don't know them, these Loewen windows ( have 1/4-inch (!) thick inner panes, weigh a couple hundred pounds each, and cost one billion dollars each (OK, I kid; but I think it was over $3,000 to have one double and one single window installed, and that was ten years ago).

Anyway, what do you think? Any experience with a better sound reducing window than the Loewen Tranquility? Any better alternative? Anything I can buy to stuff in the window frames and absorb sound in a reasonably aesthetically pleasing package (in my weaker moments, I envision apparatus involving velcro and very thick felt pads in designer colors).

Thanks in advance,
Loewen window specs look good but I would see about replacing the argon gas with krypton gas. Argon gas is 20% denser than air and krypton is 90% denser than air. I replaced my windows 3 years ago with Great Lakes Uniframe Maxuus 10. They are triple pane krypton gas filled. Really helped a lot for noise and fantastic efficiency. They have an U factor of 0.20 for double hung an U factor of 0.18 for casement and picture windows. Average list price was for me just over 1200 each. Price depends on size.
I would guess that overall it is a great idea. Our double-pane glass makes a significant difference when you close the windows. BUT, the low notes of performance car exhaust that you are complaining about will probably be the less effected end of the audio range that they are able to block out. At least that's been my experience with our windows. I have no idea what gas they use inside (per the above suggestion). You may also want to consider sound barrier curtains, which unfortunately seem to usually be quilted. There was also a company in VT that made quilted shades that ran on tracks on either side of the window and effectively sealed the windows shut - those were primarily for insulation but I noticed they also have a huge impact on sound (my parents had them at their house and you could never tell when a car had arrived when those shades were down, which was not the case when they were up).
Inside shutters?
Windows? What's that? I live in a cave. Best scenario for resonance elimination. Though the bats insist on nesting in my acoustic ceiling deadeners.
Vandermeulen, does the bats' sonar affect your systems' performance? If so, for good or ill?
Jim...I'm not saying. Its a secret that I'm about to put into production and sell as a "tweak". Though, I havent quite figured out a way to glue those little suckers onto the top of the amps without cooking them. DEFINITELY not for Class A.
Argon or Krypton gas is really mainly beneficial for solar heat gain and loss. For sound control, air (or even better a vacuum) is preferred, so stick with the Loewen argon gas.....they've done their tests.
The 40 STC rating they achieve is pretty good and the keys to this result are the reasonably large air space (21mm compared to industry standard 12mm), and the use of laminated glass for the internal glass skin.
To REALLY control sound through glass, you would need an air/vacuum gap of 1" minimum and 2 sheets of 1/2" to 3/4" laminated glass so this is mostly impractical in residential dwellings.
The Loewen system as I mentioned, allows both sound AND solar benefits. If you wanted only the acoustic reduction, you could achieve the same results with a single skin of 3/4" LAMINATED glass (1/2"+1/4").
I will be looking into this myself shortly. I do not know what kind of windows I will be installing. Here in Boston if you live next to Logan Airport, Massport installed windows that reduced the sounds of planes going by. If they are affordable I think they should do the job for me.
Double paned windows help a great deal, no doubt about it. But you may get even more benefit from siding with a cement board product such as Hardi-plank and insulating your walls. I recently built an addition with basic Andersen two paned windows, R-13 fiberglass in the walls, and Hardi-plank on the exterior. It won't drown out the mufflers entirely, but it is amazingly quiet in there. Addressing just the windows focuses on too small a square footage. Your walls are most likely transmitting most of the noise; they comprise a much larger area.
Smata67, thanks for that idea ... however, I live in one of those traditional, old Chicago buildings that has a "thrust" sunroom at the front of the living space (an example; not my place but similar, just remove that arch). The exterior walls of my living room (which is my stereo room) have seven windows over three short spans; roughly 40% to 50% or more of that area is glazed. The side wall extending back is made of 85-year old Chicago brick and I doubt you could hear a boiler explosion through it.
Some kind of interior treatment for the windows would give the best bang for the buck, I think. Here's another idea. My mother lives on the six floor of a condo building with a busy street down below in Miami and one thing I have noticed is how much more quiet the room with the balcony is. The structure tends to block noise from hitting the sliding glass door, since it is between the source and the window. If you could simulate something like that, perhaps with some flower boxes extending out a couple of feet, it might help some.
As a studio owner, I have been through this. We spent lots of $$ on sound reduction. The laminated glass between the 2 rooms cost around $4k. This was 1" laminated and 3/4" laminated.
I was going to have outside windows but decided not to since there would be no way of getting STC ratings above 35 or so. The best ones that I saw were Milgard Quiet Line.
I would suggest either 2 things... Use double set of windows with about 6" air space or use a rigid fiberglass insert that will fit into the window frame. The only thing that will stop sound is air space and mass.
You can look on my website for pictures of the fiberglass insert. It's removable and we placed them behind plantation shutters.